Nogales police say public works employees hauled out an estimated 39 pounds of pot while investigating a clogged sewer line Wednesday.

Investigators told the Nogales International newspaper that the bales were smaller than the size of a suitcase and tied to 900 feet of rope in a narrow pipe that connects systems in the U.S. and Mexico.

Police Lt. Carlos Jimenez says it's the first time they've discovered marijuana tied to a rope they believe smugglers were planning to maneuver through the line.

Police say a search at the Rio Rico sewer plant, where the feed ends, did not turn up more drugs.

The drugs' street value was estimated at more than $20,000.

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